Enucleated human polymorphonuclear leukocytes (PMN) were prepared by centrifuging isolated, intact PMN over a discontinuous Ficoll gradient that contained 20 microM cytochalasin B. The enucleated cells (PMN cytoplasts) contained about one-third of the plasma membrane and about one-half of the cytoplasm present in intact PMN. The PMN cytoplasts contained no nucleus and hardly any granules. The v...

Objective—Previous studies demonstrated that uncoupling protein 2 (UCP2) plays a negative role in modulating leukocyte inflammatory responses. The mechanism underneath the role of UCP2 in modulating leukocyte inflammatory responses, however, is incompletely understood. Here, we investigated the effect of UCP2 in polymorphonuclear leukocyte (PMN) chemotaxis. Methods and Results—First, we assesse...

C igarette smoking is a major risk factor in the development of pulmonary emphysema, a chronic disorder thought to be caused by excess protease activity in lung. Although inhalation of cigarette smoke is associated with accumulation of polymorphonuclear leukocytes (PMN; a major source of preformed proteases) in the lung, cigarette smoke, by itself, is not chemotactic for PMN. Since alveolar mac...

Extensive studies have shown the polymorphonuclear leukocytes (PMN) dysfunction inextricably links to parturition. To investigate the effect of parity on PMN function, phorbol 12-myristate 13-acetate (PMA) stimulated luminol-amplified chemiluminescence (CL) and viability of blood and milk PMN were investigated in primiparous and pluriparous dairy cows during periparturient period. The CL kineti...

OBJECTIVE Previous studies demonstrated that uncoupling protein 2 (UCP2) plays a negative role in modulating leukocyte inflammatory responses. The mechanism underneath the role of UCP2 in modulating leukocyte inflammatory responses, however, is incompletely understood. Here, we investigated the effect of UCP2 in polymorphonuclear leukocyte (PMN) chemotaxis. METHODS AND RESULTS First, we asses...

Cationic protein purified from rabbit peritoneal polymorphonuclear leukocytes (PMN) was demonstrated to incite autoaggregation of the rabbit PMN and promote adhesiveness of human PMN to endothelial cells. PMN aggregation induced by supernatants derived from secretory PMN was blocked by a specific anticationic protein antibody. These studies reveal that a positively charged protein derived from ...

One of the cardinal signs of acute inflammation is neutrophil (PMN) emigration across the endothelium and into the affected tissue. We have previously shown that human PMN migration across human umbilical vein endothelial cell (HUVEC) monolayers is dependent on PMN-derived elastase. However, whether migrating PMN release elastase into the extracellular milieu or retain it on the cell surface is...

The vasoocclusive process in patients with sickle cell disease (SCD) is complex and involves interactions among sickle erythrocytes (SS-RBC), vascular endothelium, and plasma and cellular components. The role of neutrophils (PMN) in vasoocclusion has not been examined. Patients with SCD appear to have chronically activated PMN. Because the first step in PMN activation is particle recognition, w...

BACKGROUND Previous in vitro studies have demonstrated that the host response to intra-abdominal infection produces increased generalized polymorphonuclear neutrophil (PMN) adherence to vascular endothelial cells (ECs), which may lead to subsequent endothelial damage, leaky capillaries, and organ dysfunction. There are scant data to demonstrate this enhanced systemic PMN adherence in vivo or th...

We examined the relationship between neutrophil [polymorphonuclear leukocyte (PMN)] influx and lung vascular injury in response to Escherichia coli pneumonia. We assessed lung tissue PMN uptake by measuring myeloperoxidase and transvascular PMN migration by determining PMN counts in lung interstitium and bronchoalveolar lavage fluid (BALF) in mice challenged intratracheally with E. coli. Lung v...